After spending almost four months behind bars, a 40-year-old Kirbyville woman accused in a fatal accident that killed two Lumberton sisters and an unborn baby is free on bail.Crystal Lummus Boyett, who is charged with three counts of manslaughter, posted her $1.5 million bail on Monday.

Boyett was allegedly behind the wheel of a speeding Camaro on Feb. 3 that collided with a Lumberton family's Nissan Murano.

Courtney Sterling, 15, her 20-year-old sister, Connely Burns, and Burns' unborn baby, Tyson, were killed in the crash. Dawn Sterling, the girls' mother, was seriously hurt in the collision and remained hospitalized for two months after the accident.

Police said the Camaro's driver was traveling at speeds near 120 mph when she hit the family's SUV.

Courtney Sterling, a freshman at Lumberton High School, had her learner's permit and was being careful not to exceed the posted speed limit of 65 mph on U.S. 96 as she drove her mom and sister to Dairy Queen for ice cream. Dawn Sterling was in the passenger seat and Connely Burns, who was seven month's pregnant with her first child, was in the back seat when the Camaro struck them from behind.

Burns and her unborn boy, Tyson, were pronounced dead at the scene.

Courtney Sterling died later in a hospital.

A little more than five minutes before the Lumberton crash, Jasper police said they clocked the Camaro traveling faster than 100 mph on U.S. 96.

Police are still investigating the events that led to the deadly collision.

In April, Lumberton police - with the help of the Texas Department of Public Safety - reconstructed the scene of the accident on U.S. 96 near its merger with U.S. 69.

Boyett's alcohol test came back negative, according to Lumberton Police Chief Danny Sullins.

Sullins said on Monday that he's still waiting for the results of her drug tests. Police found prescription Xanax inside the Camaro on the night of the accident.

Until the results are back, Hardin County District Attorney David Sheffield cannot send the case to a grand jury.